The present specification relates to a coil substrate. A coil substrate according to one embodiment of the present specification comprises: a substrate; and a coil which is mounted on one surface of the substrate and comprises a plurality of turns, wherein the plurality of turns comprise a first inner turn located at the innermost side of the coil and a first outer turn located at the outermost side of the coil, wherein the first inner turn comprises a greater number of patterns than the first outer turn.